Fluid composition



UNITED STATES PATENT OFFICE George L. Doelling, S Wagner Electric Cor corporation of Dela 1,960,298 FLUID COMPOSITION t. Louis, Mo., assignor to poration, St. Louis, Mo., a ware No Drawing. Application July 22, 1933, Serial No. 681,764

3 Claims.

-My invention relates to a fluid composition suitable for use in fluid draulic actuating equipment for As is known, fluid pressure devices such as hyvehicle brakes.

speeds and brake diameters),

and a low solidifying point. It is also important that it not adversely affect the rubber piston sealing elements or be corro the kind used in the manufacture of fluid conduits.

been proposed to utilize as a tus, including the It has heretofore hydraulic brake fluid, a mixture monoethyl ether of sive to metals of the apparaof castor oil and ture does not meet the above requirements reused. 50% castor oil and 50% of this viscosity characteristics In a mixture of glycol ether, the

are satisfactory but the fluid causes the rubber piston sealing cups to swell and to otherwise deteriorate, especially at high temperatures.

Reduction of the content to approximately 35% eliminates practiviscous for operating purposes,

particularly under conditions of low temperature.

I have conceived the idea of forming a fluid der of the fluid to employ another liquid which is the freezing point substantially below zero. The toluene sulfonyl ethylamid used is a mixture of ortho toluene sulfonyl ethylamid and para toluene sulfonyl ethylamid. The methyl derivatives can also be used. In place of the ethyl deriva tives other alkyl derivatives can be used when the alkyl group has less than 6 carbon atoms. Also, there is advantage in using amid derivatives of two or more difierent alkyl groups, as for instance, approximately 5% by volume of each of ortho and para toluene sulfonyl ethylamids, and approximately 2 by volume of each of the ortho and para toluene sulfonyl methyl amids can be used in place of the of toluene sulfonyl ethylamid in the above example. Instead of potassium arsenite as an agent for neutralization of acidity, other substances such as potassium hydroxide can be us Having fully described my invention, what I claim as new and desire to secure by Letters Patent of the United States is: I

1. An operating liquid for fluid pressure apparatus comprising castor oil, a mixture of toluene sulfonyl alkyl amids, (the alkyl group havether of ethylene glycol.

2. An operating liquid for fluid pressure apparatus comprising castor oil in substantially 50 parts by volume, monoethyl ether of ethylene glycol in substantially parts by volume, and a mixture, in approximately 15 parts by volume, of ortho toluene sulfonyl alkylamid and para toluene sulfonyl alkyl amid, the alkyl group in each case having less than 6 carbon atoms.

3. An operating liquid for fluid pressure apparatus consisting of castor oil in substantially parts by volume, monoethyl ether of ethylene glycol in substantially 35 parts by volume, approximately 5 parts of an ortho toluene sulfonyl alkyl amid, 2 parts of another ortho toluene sulfonyl alkyl amid, 5 parts of a para toluene sulfonyl alkyl amid, 2% parts of another para toluene sulfonyl alkyl amid, (the alkyl groups of said amids having less than 6 carbon atoms), and an acidity neutralizing agent.

GEORGE L. DOELLING. 

